In Sinister 2, the film departs from the use of Super 8 footage like its predecessor, instead incorporating various found footage mediums including vinyl records, a ham radio, and 16mm film. The eerie tale initiates with a chilling 16mm home movie showing three individuals bound to crosses in a desolate cornfield. Suddenly, one of these crosses ignites, resulting in a horrific death.
The story unfolds with Deputy So & So, previously seen in the first film, now navigating life outside the law enforcement. He frequents a Catholic confession booth, where it becomes evident he has left his role as a deputy following the harrowing Oswalt case. Instead, he has taken on the mantle of a private investigator and spends his time extinguishing properties he suspects have been tainted by the sinister presence of Bughuul.
Meanwhile, we meet Courtney, a devoted mother to twin boys, Dylan and Zach, as she faces terrifying trials. While shopping, she suddenly finds herself being stalked by an unscrupulous pervert employed by her abusive ex-husband to locate her family. In a tense escape, she makes her way to a rotting farmhouse that has offered them refuge for some time. Here, young Dylan is plagued by nightmares, aided by his unsettlingly not-so-imaginary friend Milo (one of Bughuul's past victims). Milo guides him through several gruesome 16mm snuff films that display families meeting their brutal ends: one tale features a family devoured by alligators (Fishing Trip), another presents a chilling scene of a family freezing to death in a snowstorm (Christmas Morning), adding visceral horror to their already grim lives.
As Zach's demeanor turns increasingly aggressive—hurling insults at his family and demonstrating violent tendencies reminiscent of their father—the tension escalates. In a fateful encounter, Deputy arrives with the intent to purge the farmhouse but is stopped by Courtney, who, upon understanding the misunderstanding, invites him in for coffee. They bond over their traumatic pasts—her son’s suffering reflecting his own childhood trauma. With shared secrets over drinks on the porch, she reveals her wish for him to be a father figure for her boys, culminating in a brief kiss that hints at a growing connection.
The next day, Deputy So & So seeks out Dr. Stromberg, who sheds light on the eerie disappearance of Professor Jonas from the first film and a disturbing HAM radio recording of a child recounting the horrors of family annihilation with the chilling phrase, > "I can't hear Bughuul over your yelling, mom!" This revelation leads to the understanding that Bughuul feeds off artistic expressions.
As Courtney and her sons face further threats from Clint, her abusive ex, and Zach falls under Bughuul’s sinister influence, the situation spirals. In a shocking twist, Zach, possessed by the malevolent spirit, films a horrific act—druing his family, tying them to crosses, and setting one ablaze with Clint as the target. The Deputy arrives just in time to intervene but faces Clint's wrath. Ultimately, Clint meets a fiery fate, yet as chaos unfolds, possessed Zach threatens their escape, supported by an unholy force of dead children wreaking havoc.
In a desperate attempt to save his newfound family, the Deputy confronts the malevolent figures and makes a heart-wrenching choice to shatter the camera trapping them all within its malevolent gaze, obliterating Zach's connection to Bughuul. Yet, despite his efforts, as they attempt to flee, the specter of Bughuul looms large.
As they drive away, haunted by the night's events, the Deputy encounters an ominous reminder of their harrowing battle—a HAM radio that unleashes the voices of the deceased children chanting ominously, hinting at the encroaching doom with chilling clarity: "It's the kids! ...DEPUTY!!!” Ultimately, it's insinuated that the evil they fought against claims another soul, leaving the audience with a lingering sense of dread and uncertainty.
